AUDIORECORD(1) User Commands AUDIORECORD(1)

NAME

audiorecord - record an audio file

SYNOPSIS

audiorecord [-af] [-v vol] [-c channels] [-s rate]
[-e encoding] [-t time] [-i info] [-d dev]
[-T au|aif[f]|wav] [file[.au|.aif[f]|.wav]]

DESCRIPTION

The audiorecord utility copies audio data from the audio device to a
named audio file, or to the standard output if no filename is
present. If no output file is specified and standard output is a tty,
the program exits with an error message.


By default, monaural audio data is recorded at 8 kHz and encoded in
u-law format. If the audio device supports additional configurations,
the -c, -s, and -e options may be used to specify the data format.
The output file is prefixed by an audio file header that identifies
the format of the data encoded in the file.


Recording begins immediately and continues until a SIGINT signal (for
example, Control-c) is received. If the -t option is specified,
audiorecord stops when the specified quantity of data has been
recorded.


If the audio device is unavailable, that is, if another process
currently has read access, audiorecord prints an error message and
exits immediately.

OPTIONS

The following options are supported:

-?
Help: Prints a command line usage message.


-a
Append: Appends the data on the end of the
named audio file. The audio device must
support the audio data format of the existing
file.


-c channels
Channels: Specifies the number of audio
channels (1 or 2). The value may be specified
as an integer or as the string mono or
stereo. The default value is mono.


-d dev
Device: The dev argument specifies an
alternate audio device from which input
should be taken. If the -d option is not
specified, the AUDIODEV environment variable
is consulted (see below). Otherwise,
/dev/audio is used as the default audio
device.


-e encoding
Encoding: Specifies the audio data encoding.
This value may be one of ulaw, alaw, or
linear. The default encoding is ulaw.


-f
Force: When the -a flag is specified, the
sample rate of the audio device must match
the sample rate at which the original file
was recorded. If the -f flag is also
specified, sample rate differences are
ignored, with a warning message printed on
the standard error.


-i info
Information: The `information' field of the
output file header is set to the string
specified by the info argument. This option
cannot be specified in conjunction with the
-a argument.


-s rate
Sample Rate: Specifies the sample rate, in
samples per second. If a number is followed
by the letter k, it is multiplied by 1000
(for example, 44.1k = 44100). The default
sample rate is 8 kHz.


-t time
Time: The time argument specifies the maximum
length of time to record. Time can be
specified as a floating-point value,
indicating the number of seconds, or in the
form: hh:mm:ss.dd, where the hour and minute
specifications are optional.


-T au | aif[f] | wav
Specifies the audio file type to create. If
the -a option is used, the file type must
match the file to which it is being appended.
Regardless of the file suffix, the type is
set as specified in this option. If this
option is not specified, the file suffix
determines the type.


-v vol
Volume: The recording gain is set to the
specified value before recording begins, and
is reset to its previous level when
audiorecord exits. The vol argument is an
integer value between 0 and 100, inclusive.
If this argument is not specified, the input
volume remains at the level most recently set
by any process.

OPERANDS

file[.au|.aif[f]|.wav]

File Specification: The named audio file is rewritten, or
appended. If no filename is present, and standard output is not a
tty, or if the special filename "-" is specified, output is
directed to the standard output.

If the -T option is not specified, the file suffix determines the
type of file. If the suffix is not recognized, the default is
.au. If the -T option is specified, that file type is used
regardless of the file suffix.

USAGE

See largefile(7) for the description of the behavior of audiorecord
when encountering files greater than or equal to 2 Gbyte (2^31
bytes).

ENVIRONMENT VARIABLES

AUDIODEV
The full path name of the audio device to record from, if
no -d argument is supplied. If the AUDIODEV variable is
not set, /dev/audio is used.

SEE ALSO

audioconvert(1), audioplay(1), audio(4I), largefile(7)

February 8, 2020 AUDIORECORD(1)